it works, I tried it

Code:
connect internal
grant execute on dbms_lock to lsc:
connect lsc

create or replace procedure sleep
as
begin
dbms_lock.sleep(90);
end;
/

variable job number

begin
dbms_job.submit(:job, 'sleep;', sysdate, 'trunc(sysdate,''mi'')+1/288');
end;
/

commit;

select next_date from user_jobs;
next_date
------------
08:14:02

select sysdate from dual;
08:14:23

exec dbms_job.run(4);

sleeps 90 seconds............

select next_date from user_jobs;
next_date
-----------
08:19:00

wait for 5 minutes for next execution

08:19:00 job starts

sleeps 90 seconds............

select next_date from user_jobs;
next_date
-----------
08:24:00

it is scheduled for every 5 minutes even the jobs takes longer than a minute